/*
 * Guifications - The end all, be all, toaster popup plugin
 * Copyright (C) 2003-2004 Gary Kramlich
 *
 * This program is free software; you can redistribute it and/or
 * modify it under the terms of the GNU General Public License
 * as published by the Free Software Foundation; either version 2
 * of the License, or (at your option) any later version.
 *
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with this program; if not, write to the Free Software
 * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
 */

/*
  2005.07.22 Modified by Hong Jen Yee (PCMan)
  This piece of code detecting working area is got from Guifications, a plug-in for Gaim.
*/

# include <gdk/gdk.h>
# include <gdk/gdkx.h>
# include <X11/Xlib.h>
# include <X11/Xutil.h>
# include <X11/Xatom.h>

gboolean
gf_display_get_workarea(GdkRectangle *rect)
{
  Atom xa_desktops, xa_current, xa_workarea, xa_type;
  Display *x_display;
  Window x_root;
  guint32 desktops = 0, current = 0;
  gulong *workareas, len, fill;
  guchar *data;
  gint format;

  GdkDisplay *g_display;
  GdkScreen *g_screen;
  Screen *x_screen;

  /* get the gdk display */
  g_display = gdk_display_get_default();
  if (!g_display)
    return FALSE;

  /* get the x display from the gdk display */
  x_display = gdk_x11_display_get_xdisplay(g_display);
  if (!x_display)
    return FALSE;

  /* get the screen according to the prefs */
  g_screen = gdk_display_get_default_screen(g_display);
  if (!g_screen)
    return FALSE;

  /* get the x screen from the gdk screen */
  x_screen = gdk_x11_screen_get_xscreen(g_screen);
  if (!x_screen)
    return FALSE;

  /* get the root window from the screen */
  x_root = XRootWindowOfScreen(x_screen);

  /* find the _NET_NUMBER_OF_DESKTOPS atom */
  xa_desktops = XInternAtom(x_display, "_NET_NUMBER_OF_DESKTOPS", True);
  if (xa_desktops == None)
    return FALSE;

  /* get the number of desktops */
  if (XGetWindowProperty(x_display, x_root, xa_desktops, 0, 1, False,
                         XA_CARDINAL, &xa_type, &format, &len, &fill,
                         &data) != Success) {
    return FALSE;
  }

  if (!data)
    return FALSE;

  desktops = *(guint32 *)data;
  XFree(data);

  /* find the _NET_CURRENT_DESKTOP atom */
  xa_current = XInternAtom(x_display, "_NET_CURRENT_DESKTOP", True);
  if (xa_current == None)
    return FALSE;

  /* get the current desktop */
  if (XGetWindowProperty(x_display, x_root, xa_current, 0, 1, False,
                         XA_CARDINAL, &xa_type, &format, &len, &fill,
                         &data) != Success) {
    return FALSE;
  }

  if (!data)
    return FALSE;

  current = *(guint32 *)data;
  XFree(data);

  /* find the _NET_WORKAREA atom */
  xa_workarea = XInternAtom(x_display, "_NET_WORKAREA", True);
  if (xa_workarea == None)
    return FALSE;

  if (XGetWindowProperty(x_display, x_root, xa_workarea, 0, (glong)(4 * 32),
                         False, AnyPropertyType, &xa_type, &format, &len,
                         &fill, &data) != Success) {
    return FALSE;
  }

  /* make sure the type and format are good */
  if (xa_type == None || format == 0)
    return FALSE;

  /* make sure we don't have any leftovers */
  if (fill)
    return FALSE;

  /* make sure len divides evenly by 4 */
  if (len % 4)
    return FALSE;

  /* it's good, lets use it */
  workareas = (gulong *)(guint32 *)data;

  rect->x = (guint32)workareas[current * 4];
  rect->y = (guint32)workareas[current * 4 + 1];
  rect->width = (guint32)workareas[current * 4 + 2];
  rect->height = (guint32)workareas[current * 4 + 3];

  /* clean up our memory */
  XFree(data);

  return TRUE;
}

void get_desktop_working_area(GdkRectangle* area)
{
  if (!gf_display_get_workarea(area)) {
    area->x = 0;
    area->y = 0;
    area->width = gdk_screen_width();
    area->height = gdk_screen_height();
  }
}
